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Purpose: To benchmark image quality and corresponding radiation doses for acute abdominal CT examination across different laboratories and CT manufacturers., Method: An anthropomorphic phantom was scanned once with local abdominal CT protocols at 40 CT scanners, from four vendors, in thirty-three sites. Quantitative image quality was evaluated by CNR and SNR in the liver and kidney parenchyma. Qualitative image quality was assessed by visual grading analysis performed by three experienced radiologists using a five-point Likert scale to score thirteen image quality criteria. The CTDI vol was recorded for each scan. Pearson's correlation coefficient was calculated for the continuous variables, and the intraclass correlation coefficient was used to investigate interrater reliability between the radiologists., Results: CTDI vol ranged from 3.5 to 12 mGy (median 5.3 mGy, third quartile 6.7 mGy). SNR in liver parenchyma ranged from 4.4 to 14.4 (median 8.5), and CNR ranged from 2.7 to 11.2 (median 6.1). A weak correlation was found between CTDI vol and CNR (r = 0.270, p = 0.092). Variations in CNR across scanners at the same dose level CTDI vol were observed. No significant difference in CTDI vol or CNR was found based on scanner installation year. The oldest scanners had a 15 % higher median CTDI vol and a 12 % lower median CNR. The ICC showed acceptable agreement for all dose groups: low (ICC=0.889), medium (ICC=0.767), high (ICC=0.847), and in low (ICC=0.803) and medium (ICC=0.811) CNR groups., Conclusion: There was large variation in radiation dose and image quality across the different CT scanners. Interestingly, the weak correlation between CTDI vol and CNR indicates that higher doses do not consistently improve CNR, indicating a need for systematic assessment and optimization of image quality and radiation doses for the abdominal CT examination., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: Lung cancer is the most common cause of cancer-related death worldwide and therefore there has been a growing demand for low-dose computed tomography (LDCT) protocols., Purpose: To investigate and evaluate the dose and image quality of patients undergoing lung cancer screening (LCS) using LDCT in Norway., Materials and Methods: Retrospective dosimetry data, volumetric CT dose index (CTDI vol ) and dose-length product (DLP), from 70 average-size and 70 large-size patients who underwent LDCT scan for LCS were included in the survey. Effective dose and size-specific dose were calculated for each examination and were compared with the American Association of Physicists in Medicine (AAPM) requirement. For a quantitative image quality analysis, noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were determined for different regions in the chest with two iterative reconstruction techniques, iDose and Iterative Model Reconstruction. Differences in dose and image quality between average-size and large-size patients were evaluated by Independent sample t test, and Wilcoxon signed rank test within the same patient group., Results: The independent sample t test revealed significant differences ( p < .05) in dose values between average-size and large-size patients. Mean CTDI vol and DLP for average-size patients were 2.8 mGy and 115 mGy.cm, respectively, with appropriate increment for the large-size patients. Image quality (image noise, SNR, and CNR) did not significantly differ between patient groups when images were reconstructed with a model based iterative reconstruction algorithm., Conclusion: The screening protocol assessed in this study resulted in CTDI vol values that were compliant with AAPM recommendation. No significant differences in objective image quality were found between patient groups., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2024.)

Introduction: Various national solutions have been considered and implemented to address the factors which limit radiographer engagement in conducting research. Nevertheless, national literature continues to suggest that radiographer engagement in research remains low. The aim of this study was to extend the existing evidence base by conducting an international survey to assess diagnostic radiographers and therapeutic radiographers involvement with, barriers to and support mechanisms for research., Methods: Data collection was obtained via an online questionnaire which was distributed by the International Society of Radiographers and Radiologic Technologists (ISRRT). The study population included an international sample of qualified diagnostic radiographers and therapeutic radiographers across clinical and academic contexts in a variety of different roles such as clinical practice, management, education and research., Results: In total, 420 diagnostic radiographers and therapeutic radiographers completed the survey. Multiple reasons were identified that were considered to inhibit respondents from conducting research. 69.3% indicated a combination of reasons for lack of engagement with research, rather than one single issue. Examples of reasons include: lack of time, insufficient research funding, limited research expertise, and lack of a suitable mentorship scheme., Conclusion: A minor segment of survey respondents indicated involvement in research activity. Lack of dedicated time to research, mentors, and funding were among the main barriers to conduct research. Further research is required to explore what solutions are available to overcoming the barriers., (Copyright © 2024. Published by Elsevier Inc.)

Background: Patients treated for lung cancer (LC) often experience locoregional failure after initial treatment. Due to technological advances, thoracic reirradiation (re-RT) has become a viable treatment option. We sought to investigate the use of thoracic re-RT in LC patients over a time period characterized by technological advances in a large, multi-center cohort., Methods and Materials: LC patients treated with thoracic re-RT in two University Hospitals from 2010-2020 were identified. Clinical variables and RT data were extracted from the medical records and treatment planning systems. Overall survival (OS) was calculated from the last day of re-RT until death or last follow up., Results: 296 patients (small cell LC n=30, non-small cell LC n=266) were included. Three-dimensional conformal radiation therapy was the RT technique used most frequently (63%), and 86% of all patients were referred for re-RT with palliative treatment intent. During the second half of the study period, the use of thoracic re-RT increased in general, more patients received curative re-RT, and there was an increased use of stereotactic body radiation therapy (SBRT). Median time between initial RT and re-RT was 18 months (range 1-213 months). Only 83/296 patients had combined treatment plans that allowed for registration of combined doses to organs at risk (OAR). Most of the combined doses to OAR were below recommendations from guidelines. Multivariate analysis showed superior OS (p<0.05) in patients treated with curative intent, SBRT or intensity modulated radiation therapy or had excellent performance status prior to re-RT., Conclusions: The use of re-RT increased in the second half of the study period, although 2020 did not follow the trend. The use of SBRT and IMRT became more frequent over the years, yet the majority received palliative re-RT. Combined dose plans were only created for one third of the patients., (Copyright © 2024. Published by Elsevier Inc.)

Background: Low-dose CT (LDCT) chest protocols have widespread clinical applications for many indications; as a result, there is a need for protocol assessment prior to standardization. Dalhousie University and Oslo Metropolitan University have a formally established cooperative relationship., Purpose: The purpose is to assess radiation dose and image quality for LDCT chest protocols in seven different hospital locations in Norway and Canada., Material and Methods: Retrospective dosimetry data, volumetric CT dose index (CTDI vol ), and dose length product (DLP) from 240 average-sized patients as well as CT protocol parameters were included in the survey. Effective dose (ED) and size-specific dose estimate (SSDE) were calculated for each examination. For a quantitative image quality analysis, noise, CT number, and signal-to-noise ratio (SNR) were determined for three regions in the chest. The contrast-to-noise ratio (CNR) was calculated for lung parenchyma in comparison to the subcutaneous fat. Differences in dose and image quality were evaluated by a single-factor ANOVA test. A two-sample t -test was performed to determine differences in means between individual scanners., Results: The ANOVA test revealed significant differences ( p < .05) in dose values for all scanners, including identical scanner models. Statistically significant differences ( p < .05) were determined in mean values of the SNR distributions between the scanners in all three measured regions in the chest, as well as the CNR values., Conclusion: The observed variations in dose and image quality measurements, even within the same hospitals and between identical scanner models, indicate a potential for protocol optimization in the involved hospitals in both countries., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2024.)

Objective: To compare a fixed-volume contrast medium (CM) protocol with a combined total body weight (TBW) and body composition-tailored protocol in chest CT., Methods and Materials: Patients referred for routine contrast enhanced chest CT were prospectively categorised as normal, muscular or overweight. Patients were accordingly randomised into two groups; Group 1 received a fixed CM protocol. Group 2 received CM volume according to a body composition-tailored protocol. Objective image quality comparisons between protocols and body compositions were performed. Differences between groups and correlation were analysed using t -test and Pearson's r ., Results: A total of 179 patients were included: 87 in Group 1 (mean age, 51 ± 17 years); and 92 in Group 2 (mean age, 52 ± 17 years). Compared to Group 2, Group 1 showed lower vascular attenuation in muscular (mean 346 Hounsfield unit (HU) vs 396 HU; p = 0.004) and overweight categories (mean 342 HU vs 367 HU; p = 0.12), while normal category patients showed increased attenuation (385 vs 367; p = 0.61). In Group 1, strongest correlation was found between attenuation and TBW in muscular ( r = -.49, p = 0.009) and waist circumference in overweight patients ( r = -.50, p = 0.005). In Group 2, no significant correlations were found for the same body size parameters. In Group 1, 13% of the overweight patients was below 250 HU ( p = 0.053)., Conclusion: A combined TBW and body composition-tailored CM protocol in chest CT resulted in more homogenous enhancement and fewer outliers compared to a fixed-volume protocol., Advances in Knowledge: This is, to our knowledge, the first study to investigate the impact of various body compositions on contrast medium enhancement in chest CT., Competing Interests: Trial registration: ClinicalTrials.gov Identifier: NCT05645796. Registered 9 December 2022., (© 2023 The Authors. Published by the British Institute of Radiology.)

Background: Artifacts caused by metal implants are challenging when undertaking computed tomography (CT). Dedicated algorithms have shown promising results although with limitations. Tin filtration (Sn) in combination with high tube voltage also shows promise but with limitations. There is a need to examine these limitations in more detail. The purpose of this study was to investigate the impact of different metal artefact reduction (MAR) algorithms, tin filtration, and ultra-high-resolution (UHR) scanning, alone or in different combinations in both phantom and clinical settings., Methods: An ethically approved clinical and phantom study was conducted. A modified Catphan® phantom with titanium and stainless-steel inserts was scanned with six different MAR protocols with tube voltage ranging from 80 to 150 kVp. Other scan parameters were kept identical. The differences (∆) in mean HU and standard deviation (SD) in images, with and without metal, were measured and compared. In the clinical study, three independent readers performed visual image quality assessments on eight different protocols using retrospectively acquired images., Results: Iterative MAR had the lowest ∆HU and ∆SD in the phantom study. For images of the forearm, the soft tissue noise for Sn-based 150-kVp UHR protocol with was significantly higher (p = 0.037) than for single-energy MAR protocols. All Sn-based 150-kVp protocols were rated significantly higher (p < 0.046 than the single-energy MAR protocols in the visual assessment., Conclusions: All Sn-based 150-kVp UHR protocols showed similar objective MAR in the phantom study, and higher objective MAR and significantly improved visual image quality than single-energy MAR., Relevance Statement: Images with less metal artifacts and higher visual image quality may be more clinically optimal in CT examination of musculoskeletal patients with metal implants., Key Points: • Metal artifact reduction algorithms and Sn filter combined with high kVp reduce artifacts. • Metal artifact reduction algorithms introduce new artifacts in certain metals. • Sn-based protocols alone may be considered as low metal artifact protocols., (© 2023. The Author(s).)

Purpose: Describe the clinical outcome of hyperfractionated re-irradiation (HFRT) in patients with recurrent or second primary (SP) head and neck cancer (HNC)., Methods: This prospective observational study included HNC patients eligible for HFRT. Inclusion criteria: age ≥18 years, recurrent or SP HNC, planned re-irradiation and ability to respond to questionnaires. Patients received 1.5 Gy twice daily, five days a week for three (palliative) or four (curative/local control) weeks, total dose 45/60 Gy. Toxicity was scored with CTCAE v3 at baseline, end of treatment, at three, six, 12 and 36 months follow-up. Health-related quality of life (HRQoL) was measured with EORTC QLQ-C30 and EORTC QLQ-H&N35, pre-treatment and eight times until 36 months. In the main outcome (Global quality of life and H&N Pain), a change score of ≥10 was considered clinically significant, and p-values < 0.05 (two-sided) statistically significant. The Kaplan-Meier method was used for survival analyses., Results: Over four years from 2015, 58 patients were enrolled (37 recurrent and 21 SP). All, but two patients completed treatment as planned. Toxicity (≥grade 3) increased from pre-treatment to end of treatment with improvement in the follow-up period. The mean Global quality of life (QoL) and H&N Pain scores were stable from pre-treatment to three months. Maintained/ improved Global QoL was reported by 60% of patients at three months and 56% of patients at 12 months. For patients with curative, local control and palliative intent, the median survival (range) was 23 (2-53), 10 (1-66) and 14 (3-41) months respectively. Of those alive, the proportion of disease-free patients at 12 and 36 months, were 58% and 48%, respectively., Conclusion: Most HNC patients reported maintained HRQoL at three and 12 months after HFRT despite serious toxicity observed in many patients. Long-term survival can be achieved in a limited proportion of the patients., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 Oslo University Hospital.)

Background: Total body weight (TBW) is a frequently used contrast media (CM) strategy for dose calculation in enhanced CT, yet it is suboptimal as it lacks consideration of patient characteristics, such as body fat percentage (BFP) and muscle mass. Alternative CM dosage strategies are suggested by the literature. Our objectives were to analyze the CM dose impact when adjusting to body composition using methods of obtaining lean body mass (LBM) and body surface area (BSA) along with its correlation with demographic factors in contrast enhanced chest CT examinations., Methods: Eighty-nine adult patients referred for CM thoracic CT were retrospectively included, categorized as either normal, muscular, or overweight. Patient body composition data was used to calculate the CM dose according to LBM or BSA. LBM was calculated with the James method, Boer method, and bioelectric impedance (BIA). BSA was calculated using the Mostellar formula. We then correlated the corresponding CM doses with demographic factors., Results: BIA demonstrated the highest and lowest calculated CM dose in muscular and overweight groups respectively, compared to other strategies. For the normal group, the lowest calculated CM dose was achieved using TBW. The calculated CM dose was more closely correlated with BFP using the BIA method., Conclusions: The BIA method is more adaptive to variations in patient body habitus especially in muscular and overweight patients and is most closely correlated to patient demographics. This study could support utilizing the BIA method for calculating LBM for a body-tailored CM dose protocol for enhanced chest CT examinations., Relevance Statement: The BIA-based method is adaptive to variations in body habitus especially in muscular and overweight patients and is closely correlated to patient demographics for contrast-enhanced chest CT., Key Points: • Calculations based on BIA showed the largest variation in CM dose. • Lean body weight using BIA demonstrated the strongest correlation to patient demographics. • Lean body weight BIA protocol may be considered for CM dosing in chest CT., (© 2023. The Author(s).)

Background: Computed tomography (CT) contributes to 60% of the collective dose in medical imaging. Literature has demonstrated that patient dose varies across regions and countries. Establishing diagnostic reference levels (DRLs) contributes to the optimization of clinical practices and radiation protection., Purpose: To survey the dose indices (CTDIvol and dose-length product) for frequently performed CT examinations from the chosen hospitals in Norway and Canada and to determine local DRLs (LDRLs) based on the collected data., Material and Methods: The survey included eight scanners from two Norwegian hospitals and four scanners from four Canadian hospitals. Dosimetry data were collected for the following routine CT examinations: head, contrast-enhanced thorax, and abdomen and pelvis. Overall 480 adult average-sized patients from Norway and 360 from Canada were included in the survey. The LDRLs were determined as the 75th percentile of distributions of median values of dose indicators from different CT scanners. The differences in dose between scanners were determined using single-factor ANOVA., Results: The LDRLs determined in Norway were higher overall than in Canada. The obtained values were compared to the national DRLs. The dose from several scanners in Norway exceeded national Norwegian DRLs, while Canadian LDRLs were below the Canadian reference levels. The differences between the means of the dose distributions from each scanner were statistically significant ( p < 0.05) for all examinations with exception of identical scanners located in the same hospital and using the same protocols., Conclusion: Observed dose variations even in the same hospital, or from the same scanner model confirmed the need for CT protocol optimization., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2022.)

Background: Administration of contrast medium (CM) is an important image quality factor in computed tomography (CT) of the chest. There is no clear evidence or guidelines on CM strategies for chest CT, thus a consensus approach is needed., Purpose: To survey the potential impact on differences in chest CT protocols, with emphasis on strategies for the administration of CM., Material and Methods: A total of 170 respondents were included in this survey, which used two different approaches: (i) an online survey was sent to the members of the European Society of Thoracic Imaging (ESTI); and (ii) an email requesting a copy of their CT protocol was sent to all hospitals in Norway, and university hospitals in Sweden and Denmark. The survey focused on factors affecting CM protocols and enhancement in chest CT., Results: The overall response rate was 24% (n = 170): 76% of the respondents used a CM concentration of ≥350 mgI/mL; 52% of the respondents used a fixed CM volume strategy. Fixed strategies for injection rate and delay were also the most common approach, practiced by 73% and 57% of the respondents, respectively. The fixed delay was in the range of 20-90 s. Of the respondents, 56% used flexible tube potential strategies (kV)., Conclusion: The chest CT protocols and CM administration strategies employed by the respondents vary widely, affecting the image quality. The results of this study underline the need for further research and consensus guidelines related to chest CT.

Introduction: Several studies have demonstrated the psychological impact of the COVID-19 pandemic on health care providers. However, there is little known about how the COVID-19 pandemic has impacted radiation therapists (RTs) in Norway or Canada. The aim of this investigation was to study the psychological impact of working during the COVID-19 pandemic among RTs in Canada and Norway., Methods: Online surveys were administered to a convenience sample of RTs and RT department managers. Approximately 2000 and 300 RTs were invited to participate from Canada and Norway, respectively. The RT survey collected information on demographics, work-related stressors, psychological impact, quality of life, and workplace support programmes. The RT manager survey collected information on departmental changes, patient volumes, staff shortages and redeployment, personal protective equipment, and infection control measures. Descriptive analysis, group comparisons and logistic regression were used to examine the impact of COVID-19 on RTs in the two countries, while open-ended questions were examined through thematic analysis., Results: Work-related stress and anxiety were prevalent among Canadian (n = 155) and Norwegian RTs (n = 124), with Canadian RTs reporting higher levels. Fear of transmission, changes in PPE usage, and changes in staffing were reported as the most frequent work-related stressors. Themes related to working during the pandemic included: generalised anxiety; physical, emotional and cognitive symptoms of stress; and loneliness, as well as negative impact on health and quality of relationships. Survey findings from RT department managers in Canada (n = 12) and Norway (n = 13) suggest that the pandemic had an organisational impact on RT departments due to implemented infection control measures and changes in staffing., Conclusion: The COVID-19 pandemic has led to similar stressors amongst Canadian and Norwegian RTs but relatively higher levels of psychological impact among Canadian RTs. Findings demonstrate the importance of mental health support programmes in the workplace to mitigate the psychological impact of the COVID-19 pandemic on RTs., (© 2021 The Authors. Journal of Medical Radiation Sciences published by John Wiley & Sons Australia, Ltd on behalf of Australian Society of Medical Imaging and Radiation Therapy and New Zealand Institute of Medical Radiation Technology.)

Introduction: While there has been strong emphasis on enhancing interprofessional education and interprofessional care in the published literature, there is relatively little literature focused on advancing interprofessional research. In extrapolating from the current frameworks of interprofessional collaboration (IPC), it becomes clear that the core competencies of IPC are transferable to research teams. The aim of this paper is to present our experience of an international research team framed within core competencies for IPC., Methods: A simplified narrative inquiry approach was used to share the experience of an international research team framed within six core competencies of IPC., Results and Discussion: By way of our international research collaboration, we demonstrate the translation of key core competencies for IPC. We share key learnings and mitigation strategies for the successful outcomes of the research team., Conclusion: To embark on a successful international research collaboration requires integrating IPC core competencies across the entire research continuum. In addition to the core competencies of collaboration, enablers to success also include digital collaborative forums, existing professional relationships and research projects that offer global meaning and value., (Copyright © 2021. Published by Elsevier Inc.)

Background: Brain metastases (BM) occur in about 30% of all patients with non-small cell lung cancer (NSCLC). BM treatment guidelines recommend more frequent use of stereotactic radiotherapy (SRT). Overall, studies report no difference in overall survival (OS) comparing SRT to whole-brain radiotherapy (WBRT). We examined survival after radiotherapy for BM in a population-based sample from the South-Eastern Norway Regional Health Authority treated 2006-2018., Methods: We reviewed electronic medical records of 2140 NSCLC patients treated with SRT or WBRT for BM from 2006-2018. Overall survival (OS) was compared to predicted survival according to the prognostic systems DS-GPA and Lung-molGPA., Results: Use of SRT increased during the period, from 19% (2006-2014) to 45% (2015-2018). Median OS for all patients was 3.0 months, increasing from 2.0 (2006) to 4.0 (2018). Median OS after SRT was 7.0 months ( n  = 435) and 3.0 months after WBRT ( n  = 1705). Twenty-seven percent of SRT patients and 50% of WBRT patients died within 90 days after start of RT. Age ≥70, male sex, KPS ≤70, non-adenocarcinoma histology, ECM present, multiple BM, and WBRT were associated with shorter survival ( p  < .001). Actual mOS corresponded best with predicted mOS by DS-GPA and Lung-molGPA for the SRT group., Conclusion: Overall survival after radiotherapy (RT) for BM improved during the study period, but only for patients treated with SRT. Survival after WBRT remains poor; its use should be questioned. DS-GPA and Lung-molGPA seem most useful in predicting prognosis considered for SRT.

Aim: To analyse the use of radiotherapy (RT) and factors affecting overall survival (OS) after RT in breast cancer patients with brain metastases., Methods: Breast cancer patients treated from 2008 to 2018 with whole brain RT (WBRT) or stereotactic radiosurgery (SRS) at a large regional cancer referral center were identified from the hospital's RT register. Clinical variables were extracted from medical records. OS was calculated from date of first RT until death or last follow up. Potential factors affecting OS were analyzed., Results: 255 females with WBRT (n = 206) or SRS (n = 49) as first RT were included. An increased use of initial SRS was observed in the second half of the study period. The most common WBRT fractionation regimen was 3 Gy × 10. SRS was most often single fractions; 18 or 25 Gy between 2009 and 2016, while fractionated SRS was mostly used in 2017 and 2018. Median OS in the WBRT group was 6 months (CI 1-73) relative to 23 (CI 0-78) in the SRS group. Age, performance status, initial RT technique, extracranial disease, brain metastasis surgery, number of brain metastases and DS-GPA score had significant impact on OS. Only ECOG 0 and brain metastasis surgery were associated with superior OS in multivariate analysis., Conclusion: WBRT was the most frequent primary RT. An increased use of initial SRS was observed in the second half of the study period. Only ECOG 0 and brain metastasis surgery were associated with superior OS in multivariate analysis., (Copyright © 2021. Published by Elsevier Inc.)

Background: We investigated the impact of varying contrast medium (CM) densities and x-ray tube potentials on contrast enhancement (CE), image quality and radiation dose in thoracic computed tomography (CT) using two different scanning techniques., Methods: Seven plastic tubes containing seven different CM densities ranging from of 0 to 600 HU were positioned inside a commercial chest phantom with padding, representing three different patient sizes. Helical scans of the phantom in single-source mode were obtained with varying tube potentials from 70 to 140 kVp. A constant volume CT dose index (CTDIvol) depending on phantom size and automatic dose modulation was tested. CE (HU) and image quality (contrast-to-noise ratio, CNR) were measured for all combinations of CM density and tube potential. A reference threshold of CE and kVp was defined as ≥ 200 HU and 120 kVp., Results: For the medium-sized phantom, with a specific CE of 100-600 HU, the diagnostic CE (200 HU) at 70 kVp was ~ 90% higher than at 120 kVp, for both scan techniques (p < 0.001). Changes in CM density/specific HU together with lower kVp resulted in significantly higher CE and CNR (p < 0.001). When changing only the kVp, no statistically significant differences were observed in CE or CNR (p ≥ 0.094), using both dose modulation and constant CTDIvol., Conclusions: For thoracic CT, diagnostic CE (≥ 200 HU) and maintained CNR were achieved by using lower CM density in combination with lower tube potential (< 120 kVp), independently of phantom size.

Purpose: The purpose of the study was to evaluate student exchange experiences to gain insight into what students perceived as benefits, challenges, and overall areas for improvement that might inform and enhance future exchange projects., Methods: A general program evaluation survey, adapted to address the project objectives, was conducted. Eight students from Norway, Canada, and South Africa participating in an international exchange project completed an online survey. The responses were coded and organized in themes such as pre-exchange preparation, home/host country support, challenges, and new learning., Results & Conclusions: Despite the challenges the students experienced, students indicated advantages such as new learning, personal development, and expanded professional knowledge. Students gained an international perspective and deeper understanding of their profession and insight into the similarities and differences in clinical practice emphasizing the importance of creating global citizens through internationalization in radiography education. These student experiences confirmed their agency in disposition, motivation, self-efficacy, and position., (Copyright © 2020. Published by Elsevier Inc.)

Purpose: Imaging phantoms can be cost prohibitive, therefore a need exists to produce low cost alternatives which are fit for purpose. This paper describes the development and validation of a low cost paediatric pelvis phantom based on the anatomy of a 5-year-old child., Methods: Tissue equivalent materials representing paediatric bone (Plaster of Paris; PoP) and soft tissue (Poly methyl methacrylate; PMMA) were used. PMMA was machined to match the bony anatomy identified from a CT scan of a 5-year-old child and cavities were created for infusing the PoP. Phantom validation comprised physical and visual measures. Physical included CT density comparison between a CT scan of a 5-year old child and the phantom and Signal to Noise Ratio (SNR) comparative analysis of anteroposterior phantom X-ray images against a commercial anthropomorphic phantom. Visual analysis using a psychometric image quality scale (face validity)., Results: CT density, the percentage difference between cortical bone, soft tissue and their equivalent tissue substitutes were -4.7 to -4.1% and -23.4%, respectively. For SNR, (mAs response) there was a strong positive correlation between the two phantoms (r > 0.95 for all kVps). For kVp response, there was a strong positive correlation between 1 and 8 mAs (r = 0.85), this then decreased as mAs increased (r = -0.21 at 20 mAs). Psychometric scale results produced a Cronbach's Alpha of almost 0.8., Conclusions: Physical and visual measures suggest our low-cost phantom has suitable anatomical characteristics for X-ray imaging. Our phantom could have utility in dose and image quality optimisation studies., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Aim: The aim of this study is to compare the absorption ability of two lead-free aprons with a lead apron., Method: The absorption ability of three aprons was measured and compared; Opaque Fusion 0.35 mm (OpaqFu) bilayer apron containing bismuth and antimony, No Lead 0.35 mm (NoLead) one-layer apron containing antimony, and a lead apron. The measurements were repeated with and without each of the aprons present in both primary and scattered beams. The selected tube voltages were between 60 and 113 kVp with constant mAs, a fixed field size, and fixed source-to-object distance., Results: No significant difference in absorption ability of the two lead-free aprons compared with that of the lead apron was observed when the dose was measured in the primary beam. When measurements were performed in the scatter radiation field, the absorption ability of the OpaqFu apron was 1.3 times higher than that of NoLead apron and nearly equal to the absorption ability of the lead apron. An increase in the difference between the OpaqFu and NoLead aprons was observed for the tube energies higher than 100 kVp in favour of OpaqFu apron., Conclusion: It is safe to use the lead-free aprons that were tested in this study in a clinical environment for the tube energy range of 60 kVp-113 kVp., (Copyright © 2018. Published by Elsevier Inc.)

Background: Although there is significant evidence that the family caregivers (FCs) of cancer patients can experience significant caregiver burden and symptoms, less is known about the relationships between FCs and patient characteristics that influence caregiver burden., Objective: The purpose of this study was to examine the effect of cancer patients' and FCs' symptoms and demographic characteristics on caregiver burden at initiation of the patients' radiation treatment., Methods: Two hundred eighty-one dyads of FCs and cancer patients who received a diagnosis of breast, prostate, melanoma, lymphoma, and head and neck cancers were recruited at the beginning of the patients' radiation treatment. Measures of depression, sleep disturbance, fatigue, social support, and self-efficacy were obtained from both FCs and cancer patients. The family caregivers were also assessed for caregiver burden. Associations between patients' and caregivers' symptoms and demographic characteristics and caregiver burden were investigated using multivariate analyses., Results: There were significant associations between caregiver burden and the patient-related variables such as self-efficacy (P = .02), sleep disturbance (P = .03), and social support (P = .04). Among FC-related variables, higher scores of depression (P < .01), fatigue (P < .01), and symptoms (P < .01) were significantly associated with higher caregiver burden. Being a female, either as a patient or FC, increased the likelihood of experiencing fatigue and sleep disturbance., Conclusion: Caregiver burden in FCs is influenced by interplay of patients' and their own symptoms and problems. These interdependencies exist from the beginning of treatment., Implications for Practice: Nurses should systematically assess the problems and symptoms of the patients and FCs and support them from the time of diagnosis to help prevent symptom development and deterioration.

Aim: To evaluate the patterns of loco-regional recurrences in head and neck cancer patients METHODS: Twenty-six out of 112 patients treated with primary or postoperative 3D CRT or IMRT for their primary and recurrent disease between 2007 and 2013 were included. The CT images of recurrent disease were rigidly registered with the primary CT images for each patient. To assess overlaps and overlap localization, the recurrence volume overlapping with the primary target volume was identified. For relapses occurring in the regional lymph nodes, the epicenter distance in recurrences and primary volumes and dose in recurrences were also identified. The recurrences were defined as in-field, marginal or out-of-field., Results: The majority of the failures occurred within 1 year after completed primary treatment. The dose differences in recurrence volume were not statistically significant when patients were treated with IMRT or 3D CRT. Recurrence in 15/26 of the included patients occurred in the regional lymph nodes located fully or partly inside the primary target volume or the elective lymph node region. The majority of recurrences were recognized as in-field, independent of the primary treatment., Conclusion: Recurrence in the majority of the patients occurred in the regional lymph nodes located in high dose area. The cause of recurrence may be due to inadequate total dose in the primary treatment and/or lack of optimal primary diagnosis leading to inadequate primary target delineation.

Background: To test seven different strategies for recruitment in a randomized controlled trial, to report documented response data from each strategy, and to discuss recruitment challenges., Methods: We used 5 opt-in (potential participants have to do something active to contact or be contacted by the researcher) and 2 opt-out (potential participants have the option to decline being contacted about a study) recruitment strategies from February 2013 until July 2014 to contact 1562 cancer patient candidates for participation in a randomized controlled trial. For each of these cancer patients a caregiver was also invited to take part in the study., Results: Of the 1562 candidates, 22.6 % were ineligible on initial contact, 56.7 % declined to participate on initial contact, and 8.9 % agreed orally to participate but did not complete the enrollment. The 2 opt-out strategies, on-site recruitment and routine care letters recruitment, yielded the highest number of recruited participants with 79 dyads and 58 dyads respectively, constituting 42.7 % and 31.4 % of the total number of enrolled candidates. The 5 opt-in recruitment approaches yielded 49 dyads for the study. Almost half of these dyads were recruited using the approach termed "relying on providers at the hospital.", Conclusions: In this study, opt-out recruitment strategies appeared to be the most effective., Trial Registration: Registration number NCT01867723 , registered February 2012.

Background/purpose: We explored the relation between coronary artery calcium (CAC) and cardiac radiation doses in breast cancer survivors (BCS) treated with radiotherapy (RT). Additionally, we examined the impact of other risk factors and biomarkers of coronary artery disease (CAD)., Materials and Methods: 236 BCS (median age 51years [range 30-70], median observation time 12years [9.2-15.7]), treated with 4-field RT of 50GY, were included and examined in 2004 (T1), 2007 (T2) and 2011 (T3) with clinical examination, blood tests and questionnaires. At T3, cardiac computed tomography was performed with quantification of CAC using Agatston score (AS). For 106 patients cardiac dose volume histograms were available., Results: The cohort-based median of the mean cardiac dose was 2.5 (range 0.5-7.0) Gy. There was no correlation between measures of cardiac dose and AS. AS was correlated with high cholesterol at T1/T2 (p=0.022), high proBNP at T1/T2 (p<0.022) and T3 (p<0.022) and high HbA1c at T3 (p=0.022). In addition, a high AS was significantly associated with hypertension (p=0.022). Age (p<0.001) and cholesterol at T1/T2 (p=0.001) retained significant associations in multivariate analysis., Conclusions: Traditional, modifiable risk factors of CAD correlate with CAC and may be important for the long term risk of CAD after RT. With low to moderate cardiac radiation exposure, a contribution of radiation dose to CAC could not be demonstrated., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Purpose: To explore the relationship between radiotherapy (RT) dose levels in the arm/shoulder region and arm/shoulder morbidity in breast cancer patients., Material and Methods: This study included 183 breast cancer patients who had received locoregional RT with or without chemotherapy and/or hormone treatment during the period 1998-2002. Individual RT dose level, reflected by dose-volume histograms (DVHs), for the shoulder joint and joining structures were obtained from archived CT-based RT plans. Individual median, mean and maximum arm/shoulder RT dose levels were extracted. Arm/shoulder morbidity was assessed 29-58 months after breast cancer treatment using the following clinical endpoints: arm pain, arm stiffness, swollen arm, use of arm, numbness, shoulder flexion and shoulder abduction difference, fibrosis and breast cancer-related lymphedema. The relationship between arm/shoulder RT dose level and these clinical endpoints was assessed by Spearman's correlation and multivariate logistic regression., Results: Ninety-one percent of the included patients had some degree of arm/shoulder morbidity. Neither mean nor maximum RT dose level was associated with clinical endpoints. However, significant correlations (p < 0.05) were found between DVHs and arm stiffness, arm pain, use of arm and shoulder abduction difference, when arm/shoulder RT dose levels were approximately 15 Gy., Conclusions: Three-dimensional conformal locoregional RT for breast cancer results in long-term arm/shoulder morbidity. To minimize this risk, large shoulder volumes receiving RT doses of approximately 15 Gy should be reduced.

Purpose: To explore very-long-term mortality from ischemic heart disease (IHD) after locoregional radiation therapy of breast cancer (BC) in relation to degree of hypofractionation and other treatment variables., Methods and Materials: Two hypofractionated regimens used for locoregional radiation therapy for BC from 1975 to 1991 were considered. Patients received 4.3 Gy × 2/week (10 fractions; target dose 43 Gy; n=1107) or 2.5 Gy × 5/week (20 fractions; target dose 50 Gy; n=459). To estimate cardiac doses, radiation fields were reconstructed in a planning system. Time to death from IHD was the endpoint, comparing the groups with each other and with age-matched, cancer-free control individuals, modeled with the Cox proportional hazards model., Results: Patients given 4.3 Gy × 10 had an increased risk of dying of IHD compared with both the 2.5 Gy group (hazard ratio [HR] = 2.37; 95% confidence interval [CI]: 1.06-5.32; P=.036) and the control group (HR = 1.59; 95% CI: 1.13-2.23; P=.008). Photon beams for parasternal fields gave an increased risk of dying of IHD compared with electron beams (HR = 2.56; 95% CI: 1.12-5.84; P=.025). Multivariate analysis gave an increased risk for the 4.3-Gy versus 2.5-Gy regimen with borderline significance (HR = 2.90; 95% CI: 0.97-8.79; P=.057) but not for parasternal irradiation., Conclusions: The degree of hypofractionation and parasternal photon beams contributed to increased cardiac mortality in this patient cohort. Differences emerged after 12 to 15 years, indicating the need of more studies with observation time of 2 decades., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Purpose: To evaluate cardiac doses in breast cancer patients with stage II/III treated with 4-field radiotherapy based on computed tomography (CT) dose planning., Methods and Materials: Based on archived CT images, whole heart and cardiac chamber radiation doses were analyzed in 216 (111 left-sided and 105 right-sided) mastectomized or lumpectomized breast cancer patients treated at a single institution, the Norwegian Radium Hospital, between 2000-2002. Individual dose volume histograms for the whole heart and for the four cardiac chambers were obtained, and mean, median and maximum doses to these structures were calculated. The dose (Gy) delivered to the 5% of the volume of each cardiac structure (D5%), and the volume percentage of each structure receiving ≥ 25 Gy (V25Gy) were reported. Normal tissue complication probability (NTCP) calculations were used to estimate the risk for ischemic heart disease (IHD)., Results: Cohort-based medians of the whole heart mean dose (Dmean) for left- and right-sided tumors were 3.2 Gy and 1.3 Gy, respectively, with similar ventricular but lower atrial values. The atrial doses did not differ according to laterality of the breast tumor. In 13 patients with left-sided cancer, 5% of the heart volume was exposed to >25 Gy. The NTCP estimates were generelly low, with a maximum of 2.8%., Conclusions: During adjuvant CT-based locoregional radiotherapy of women with breast cancer, the cardiac radiation doses are, at the group level, below recommended threshold values (D5% < 25 Gy), though individual patients with left-sided disease may exceed these limits.

Purpose: To assess the impact of using breathing adapted radiotherapy on contralateral breast (CB) dose, to relate the thorax shape with the dose to the organs at risk (OARs) and to predict the risk for induced malignancies in CB using linear and non-linear models, following tangential irradiation of breast., Material and Methods: Sixteen patients with stage I-II breast cancer treatment planned with tangential fields using deep inspiration breath hold (DIBH) and free breathing (FB) techniques were included in this analysis. The dose results mainly based on DVH analysis were compared. Four parameters were defined to describe thoracic shape. Excess relative risk (ERR) for cancer induction in CB, employing linear and non-linear models was calculated., Results: Average CB volumes exposed to a dose of 1 Gy is 1.3 times higher in DIBH plans than in FB plans. No significant difference in average V3Gy and V5Gy for DIBH and FB plans is observed. The average mean CB dose for DIBH and FB plans is 0.33 and 0.28 Gy, respectively. No correlation between thorax shape parameters and mean OARs dose is observed. The estimated average mean ERR with linear model is lower in FB plans (0.12) than for the DIBH plans (0.14). The estimated ERR with non-linear model is 0.14 for DIBH plans and 0.15 for FB plans., Conclusion: No significant difference in CB dose between DIBH and FB plans is observed. The four thorax shape parameters defined in this study can not be related to the dose at OARs using DIBH and FB radiation techniques. The ERR estimates for secondary CB cancer are nearly the same for FB and DIBH planning when using a linear and non-linear risk prediction models.

Purpose: To investigate the impact of using different radiation therapy techniques on contra-lateral breast (CB) dose, and also dose to other involved organs at risk such as heart and lungs following radiation therapy of breast and regional lymph nodes. Furthermore, to predict the risk for induced malignancies in CB using linear and non linear models., Material and Methods: Eight patients with stage II-III breast cancer were included in this analysis. It was focused on three treatment techniques; conventional radiotherapy technique forwardly planed, IMRT and volumetric modulated arc (RapidArc) techniques, inversely planed. The CC algorithm was employed to calculate the standard treatment plans whereas for the IMRT and RapidArc treatment plans AAA algorithm was adopted. The dose results based on mostly DVH analysis were compared. The excess relative risk (ERR) for cancer induction in CB, employed both linear and non-linear models, was estimated., Results: A better homogeneity and conformation in PTV was observed in the RapidArc plans. The highest minimum dose to PTV was observed in the conventional plans while no difference was observed for minimum significant doses D(98%) and D(99%) where D(X%) is the dose received by X% of the PTV volume. In terms of organ sparing, the IMRT and RapidArc plans spare ipsilateral-lung better, but a 40% lower mean dose in the contra-lateral lung in the conventional plans is observed. The mean dose to the contra-lateral breast was lowest for the RapidArc plans as well as the V(10Gy) and the maximum dose. The mean predicted ERR for the eight patients were lower for the conventional and RA plans than for the IMRT plans assuming a linear dose-risk relationship. The mean predicted ERR when using a non linear model was lower for all the three techniques (with lowest ERR for RapidArc plans)., Conclusions: From a clinical perspective, it should be concluded that all three solutions investigated in the study can offer high quality treatment of patients. Further comparative analysis of the two algorithms used in the present study, however, should be performed especially on the peripheral organ dose. The impact of CB exposure to a low-dose radiation on minimizing the risk of radiation induced malignancy in CB can be interpreted differently when using linear or non linear models to predict ERR. In general, no detriment was observed when using RapidArc compared to conventional treatments while a potentially higher risk could be associated to IMRT treatments with fixed gantry.

Purpose: To facilitate a discussion about the impact of dose heterogeneity on the risk for secondary contralateral breast (CB) cancer predicted with linear and non linear models associated with primary breast irradiation., Methods and Materials: Dose volume statistics of the CB calculated for eight patients using a collapsed cone algorithm were used to predict the excess relative risk (ERR) for cancer induction in CB. Both linear and non-linear models were employed. A sensitivity analysis demonstrating the impact of different parameter values on calculated ERR for the eight patients was also included in this study., Results: A proportionality assumption was established to make the calculations with a linear and non-linear model comparable. ERR of secondary cancer predicted by the linear model varied considerably between the patients, while the predicted ERR for the same patients using the non-linear model showed very small variation. The predicted ERRs by the two models were indistinguishable for small doses, i.e. below approximately 3 Gy. The sensitivity analysis showed that the quadratic component of the radiation-induction pre-malignant cell term is negligible for lower dose level. The ERR is highly sensitive to the value of alpha(1) and alpha(2)., Conclusions: Optimization of breast cancer radiation therapy, where also the risk for radiation induced secondary malignancies in the contralateral breast is taken into account, requires robust and valid risk assessment. The linear dose-risk model does not account for the complexity in the mechanisms underlying the development of secondary malignancies following exposure to radiation; this is particularly important when estimating risk associated with highly heterogeneous dose distributions as is the case in the contralateral breast of women receiving breast cancer irradiation.

Purpose: To measure the dose distribution in the contralateral breast (CB) following radiotherapy of the breast and regional lymph nodes by a 4-field technique, and to examine whether related treatment planning calculations of CB doses reproduce the measurements., Materials and Methods: CB doses were measured by thermoluminescence dosimetry on the surface of 8 patients and in an anthropomorphic phantom. Dose calculations at corresponding points of interest were performed by the treatment planning system Helax-TMS 6.1 using the pencil beam or the collapsed cone algorithm., Results: The measured CB doses were typically between 1% and 15% of the prescribed dose. The dose decreased significantly both in the medial-lateral and cranial-caudal direction. The average ratio of the measured to the calculated CB dose was about 0.7 and 0.9 for the pencil beam and the collapsed cone algorithm, respectively. One of the treatment fields aimed at the regional lymph nodes and some of the chest wall gave the highest contribution to the CB dose., Conclusions: The dose distribution in the CB following locoregional radiotherapy of the breast and regional lymph nodes is quite inhomogeneous. The collapsed cone algorithm may be used for estimating doses to the CB. Some concern is raised regarding the current field arrangement and the consequences for the CB dose.